Variable-discharge pump



April -1o\ 192s. 1,665,692

' O. H. ENSIGN VARIABLE l DISCHARGE PUMP I nvenor @Wfl/2265. 73W@ 2 Sheets-Sheet 2 o. H. ENslGN VARIABLE DISCHARGE PUMP Filed April 8, 1925 aa 37 -K lll/l/I//IVl//I//-/Z IApril 1o, 192s.

-30 with great precision. Such precision can Patented Apr. 150, 14928 UNITED sTATEs DEVILLE H.' ENSIGN,

i 1,665,692 PATENT oFEICE.

F PASADENA, CALIFORNIA, ASSIGNOR TO ENSIGN CABBURETOB COMPANY, 0F LOS ANGELES, CALIFORNIA, A CORPORATIQN 0E CALIFOBNI.

VARIABILE-inmensa@ Puur.

lApplication led April 8,

may be adjusted to furnish positively measured portions of fuel to the cylinders ot' internal combustion engines irrespective of the Y 'size of c linder or the quantities necessary to furnis propel' combustion at light loads and with extremely small cylinders.

Heretofore great diiiculty lias been encountered in the operation of small internal combustion engines .of Diesel or semi-Diesel type, and such types of engines have. been measurably limited to rather large cylinders by the previous types of umps.. This defect was llargely due to the iiculty in controlling the quantitybf fuel at the lighter loads had by manual adjustment under'control of the operator through the medium of certain mechanism which I have invented for the purpose. V An object is to build a much cheaper pump for heavy duty VDiesel or automotive type of engines, and to makesch pump self-lubrieatingV and non-leaking and free from stuifing boxes. Y

Another o )ject is to provide. apump of tliis character which will not become air bound and to so construct such pump that yan air that does" reach the pump will quickly be discharged.

The invention is broadly new, Ybasic and pioneer in thatfthe means for accomplishing the accurate measuring of quantities of'fufel discharge is obtained by providing and suitably -inanipulatingmeans for rotatably ad- V-justing in its barrel, a `plunger havinga beyeled or'miter ,end in relation to a port in said barrel toshear off the entering liquid, and to supply such liquid from a constantlevel su ply chamber. f I provide means for accurate y to provide means for accuf '2, and a. guide bearin 3.

iaas.v ser'iai No. 21,552.

adjusting the beveled end of the plunger. to properly time the beginning ef@ discharge of the liquidv when operating the pump at fullv stroke, :uid I also provide simple means for returning ,leakage from the pump plungers to the original constant level chamber.

An object is to facilitate the assembly and repair of the pump. f

The invention may be variously. a lied for use with a single lunger or with any number of plungers and may be constructed with any form of attachment of governors or other appliances, all of which are readily Y understood in the' art and will not be detailed herein. y

The plungers may be operated by any suitable mechanical contrivance and will be shown herein as operated respectively by suitable cams.

The' pump herein shown and described is a continuation in part of myco-pending ap plication, -iiled August 24, 1920, Serial No. 405,720, for improvement in automotive art, Patent #1,536,730. y Other objects, advantages and'features ot mventionmayl appear from the accompany' ing drawings, the subjoined detail description and the appended claims.

- The accompanying drawmgs illustrate the be 1 invention.

Figure 1 is a mid-section Aof va fuel pump constructed in accordance with my invention, as applied fcr usein connection with a .four cylinder engine. The section is takenlongitiidmallv of the cam shaft and plungers on line w1, lig's.` 2 and 3.

rFig. 2 is a plan view, with the cover 'to the cam shaft chamberremoved, and a portion of the cam shaft is removed to ex ose the 'top of one of the plungers and its a justing means. Fig. 3 is a section on line ai, Figs. land 2. Fig. 4 is what may be termed a rear elevation on small scale, with fuelV chamber shown in ivertical longitudinal section on line w,Fig.3. l

In`v the form shown in the drawingsthe pump frame is a singley casting' comprising a head l provided with the desired number of barrels lformed with a lunger chamber.

aid pump frame isalsovprovided wit a supply chamber 4 communicating through a suction port 5 with a pump bore 6 fromv which the dis--r charge port opens, and such port? is 1o cated transversely opposite the inlet bore 5; said frame is also provided with a valve chamber 8v to accommodate a check valve 9 for closing the outlet port 7. A spring 10. is held in place by a union 11 to hold the valve 8 seated to close the outlet bore 7. A, pump plunger 12 tightly fits'the bore 6.A o The plunger12 is provided With a beveled or mitered end affording a plane oblique face 13 adapted to form a cut ,ofl for the inlet port 5 depending vupon the rotative position of such plunger, this plane being -so lo' cated`v that with the plunger in its lowest position it maybe rotated to completely cut oli'l the suction port 5 or to completely open the same with the fraction of a revolution of the plunger Without closing the outlet4 port 7. V g

The diameter of the inlet 5 ispreferably but ak fraction ofthe diameter of thebore 6, thus to accommodate the pump tothe operation o'f the plunger, and lto form only a small leakage edge when it is closed. If this suction h'ole, is too large with. reference to' the plungerl diameter there is but a limited range Zof,"control*o't'afuel.

The upperlportiomof .the pump "boreis enlarged ."at114to'if'accommodate' a guide .15` for an upper, enlarged portion 16 of the plunger 12 to .furnishbearing surface andto take the'thrust cfa caml7 tha-tdep'resses the plunger. against the yielding resistance of spring 1,8 through a bearing cap -19 which is pinnedgto the plunger by meansof a pin 20.' The l'enlarged portion 16 of the plunger 12 is providedlwith a key-way 21, which' is engaged fby 'means of a fixed key 22in the adjusting plate 23 which is movably mounted'upon an upper flanged portion24 of the'v guide 15 and is adjustably attached thereto by means of a screw 25..

The flan e portion 24 of -the guidel is also provi ed -With a sector of a gear 26 which is arranged to meshwi'th 'a rack 27 which operates longitudinally and engages the sectors 26' of alltheplungers.`

The rack4v 27 has one end 28 which projects through the cam shaft case 29 and is movably connected to a level' 30 throughapin 31; the lever 30 being connected through a link 32 and pins 33, 34, with the pump frame 1 to forma fulcrum for operating the rack 27. Said levermay he 'operated through any suitable means'connected ata pin-hole35. Belaring-,plates'27 secured to the camshaft case 29 by screws 27 form bearings for theraek 27 and maintain such rack in operative'lpo'sition with the gears 26. The v'earn shaft lca s'e 29- is openV top and bottom andi bolted tothe pump frame by means of bolts 36 and-is covered'at the top by means` of a cover 37 held in place by cap `screws 38.y Each;A end of this cam shaft case l 29 fis .provided vvith 'ball ybearings 39held inplace by a; plate 40' and capyscrews 41'.V i lA camshaft 42 operates in the ball bearings 39 to drive the cams 17 ivhich are shown as leccentrics formed onl the shaft 42 and said cams engage the bearing caps 19 and operate to depress the pump'l plungers-y -12 against the tension of the springs 18, which return the plunger-s when rotation of the cams' permit. y

bracket 44 for supporting th-e completed pump in any suitable position on an engine or other apparatus. The cam shaft 42 is provided with a sprocket 45v for suitable attachment to any portion of any moving machinery with which the pump may be used to thus rotate the fshaft.

The cam shaft case 29 isprovided with a i The supply chamber' 4 is provided )Vith an inlet 46 by means of-which any suitable connectlon can be made to any sort` ot 'supplytank. .This connection communicates through a strainer 47 to a valve cage 48 and a valve 49 to regulate the level of the liquid, in the'supply chamber .4 through theme- 'dium `of a ,lever 50 and a float 5l attached to a fulcrum pin 52 to close the valve 49 when the :liquid has'. reached the desired height in 'the supply chamber 4; AThe valve cage 48' is threaded into the supply chamber 4 at 53 and theupper end of the cage is threaded at 54 .to receive the nut 55 tohold the lfuel connection' 46 in position. The fuel Supply chamber 4 is held in position on the flange frame 1 by means of screws 56.

Means are' provided whereby any leakage from around'the pump plungers 12 will be returned to the constant level chamber 4, and such means comprise a passage 99 leading from the bottom of the guide bearing 3 to the chamber 4. It is apparent that any liquid that may leak by the plungers 12 will accumulate in the bottom of the guide bearing 3 and be returned by gravity to the chamber 4 through the passage 99.

In practical operation the pump will be driven through means ofthe sprocket 45 or other suitable means to the correct speed to time it for the purpose involved. Cams Will be mounted at different radial positions` on the cam shaft 42 to give the desired timing of the impulse from each pump plunger discharge. The pump will be assembled and the gear 26 properly meshed with the rack 27, but for equal timing of thev relation of the discharge of the'individual pump cylinders the position of the key 22 ywith refer` ence vto the rack 27- and cut-olf face 13 can be'accurately adjusted by meansof the plate V23 and the screw 25. The pump being prop-- erly assembled and timed, and with the cam ammessa of cut-off of the suction inlet to the pump reached th cylinder'which occurs with diierent angular positions o the beveled surface 13. In Fig. 3 the -pump plunger is shown in its lowest position and with the position of the rack such that it will give the maximum amount of liquid discharge per stroke. That is to say, that the plunger being turned to a position where it will close the suction inlet port 5` at the earliest possible position in its downward stroke. This is illustrated by thel different positions of a, b, c, d; d is in the extreme upward position which showsl the position in which the uel is flowing into theV pump cylinder 6. As'the plunger descends the excess fuel which has rushed in to fill the vacuum formed by the lifting of the plunger is forced out the suction inlet 5 until the point of the plunger has passed the port 5 sealing it against further discharge of fuel back to the supply chamber 4. Further downward movement, until the plunerhas le lower position shown.' y the plunger-, forces the liquid tothe desired poi-nt of use throughthe check valve 9, and a connection, not shown, thatl may be secured to union l1.

,'If, however, the plungers are turned through an angle ever so small from the one shown on the drawings the time of point .of

@closure ofthe suction port 5 is delayed and during a longer portion ofthe travel the i' liquid will be discharged back through 5 until it can be seen that were. the plunger rotated throughulSO" no liquid at all rwould fuid passed through the 'beforced through the check valve91as it would all go back into the'supply chamber 5 and it can therefore be seen that at any'point between these two positions a relativel frac-Y tional amount of liquid will be disc arged through the check valve9 making it possible to control the charge ofthe mass of liq- 'check 'valve from full capacity 'of the plunger stroke after closing theport 5 to any small amount down to absolutelyV the zero How. This is accom- .plished with extreme accuracy because after the plunger passes the port 5 there is no possible chance for any more liquid to get in, and verys'mall possibility of anyleakage.

,It will be apparent that my invention may be used to force lubricant or liquid fuel to engines, or may be used for an purpose where a pump is desired to force iquid to a distant point.

.,Iclaim:

`1. In a pump comprising a cylinder hav'- ing inlet and discharge' ports anda reciprocating plun er formed with an obliqueface .and` adapte to form a cut-off for said inlet 4 port; and rack and gear means to effect and maintain a rotative adjustment of the plun er with relation to the inlet port.

2. e combination with a cylinder havxthe pump.

ate in said cylinder to cut oi the inlet port v and to force liquid out of the outlet port; a check valve for the outlet port; means to reciprocate the plunger; means iixed'to the 'plunger; and means adapted to be. manually loperated to control said fixed means and rotate the plunger.

3, In a ump comprlsing a barrel havingv a bore, a p unger in said bore, said bore having inlet and discharge ports, a supply chamber communicatingwith saidinlet port, an

oblique face on said plunger adapted to form a variable cut-olf for said inlet port, a gear on said plunger; and means engaging sai gear to rotate said gear and plunger to vary the time of cut-oil ofA said inlet port.

, 4. In a pump comprising a barrel having a bore, a plunger in said bore, said bore alsy having inlet and discharge ports, a supply chamber communicating 5 with said inlet port, an oblique face on said plunger adaptv'edto form a cut-oil for said inlet port, a gear on said plunger; means engaging said gear to. rotate said gear and' plunger to vary th e time of cut-0H of said inlet port; and

means to rotatabl adjust said plun er in said gear to time t e delivery of liqui from 5. In a ump comprising a barrel having a bore, a p unger in said bore, vsaid bore having inlet and discharge ports, a supply chamber communicating with said inlet port, an oblique face on said plunger .adapted to form a cut-off for said inlet port, a gear on said plunger; a rack engaging said ear and means to reci rocate said rack to,

rotate said gear and plunger, to vary the time of cut-0E of said inlet port'.

-6, In a pump comprising'a a bore, a plunger in said bore, ing inlet and discharge orts, a supply chamber communicating wit said inlet port, an

oblique face onl said plunger `adapted barrel havingy said bore havform a cut-off for said inlet port, a. gear on said plunger; means engaging said gear to 1 A rotate said gear and plunger to vary the time of cut-off of said inlet port; a cam engaging said plunger, means to rotate said cam; and spring means acting to return said plunger.

7. In a bore, a plunger 1n saidbore, havinginlet and said bore discharge ports, a supplyI a pump comprising a barrel having I chamber communicating withsaid inlet port,

an oblique face on saidplunger adapted to form a. cut-oi for said inlet port, a gear on. said plunger; means engaging said gear to rotate said gear and plunger to vary the time of cut-o of saidvnlet port; an' adjusting late secured to said plunger; and means a justably securing said plate to said gear.

8. n a pump comprising a barrel having a bore, a plunger in said bore, said bore having inlet and discharge ports, a. supply chamber communicating with said inlet perf, au oblique face on said plunger adapted to form a cutoff for said inlet port, a gear on said plunger; means engaging said geur to rotate said gear and plunger to vary the time of eut-eff el said inlet port; an adjusting plate Vsecured to said plunger; said plaie having a slot formed therein and a Set screw extending through said slot into said gea-r.

9. In a pump comprising a barrel having a bore, a, reciprocating plunger in said bore, said bore having vinlet and discharge ports, a supply chamber connnunicating with said inlet port, means whereby rotation of saidl plunger will vary the discharge of said" pump, means to reciprocate said plunger, a guide. bearing for said plunger; and means -aeeaeea adjacent said guide bearing adapted to re-1 turn the leakage past the plunger to the supply chamber.

10. In a pump comprising a barrel having a bore, a reciprocating plunger in said here` said bore having inlet and discharge ports,

ORVILLE H. ENSIGN. 

